A US military space drone landed at the Kennedy Space Center in Florida on Saturday after nearly two and a half years in orbit, Boeing said.
The unmanned X-37B shuttle, whose first flight took place in 2010, has now spent a total of more than 10 years in space and flown more than 1.3 billion miles during six missions.
"This mission highlights the Space Force's focus on collaboration in space exploration and expanding low-cost access to space for our partners, within and outside of the Department of the Air Force,"
Launched in secrecy, the X-37B was designed for the Air Force by United Launch Alliance, a joint venture between Boeing and Lockheed Martin.
It is 30 feet long, has a 15-foot wingspan and is powered by solar panels.Before the shuttle's last launch, in May 2020, the Pentagon evoked a series of scientific experiments it would undertake.
The mission was to test how certain materials react in space, to evaluate how ambient radiation in space affects a series of seeds, and to transform solar radiation into radio-electric energy.